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1.
Zusammenfassung Mit Hilfe von autoradiographischen und elektrophoretischen Methoden wurde die Dottereinlagerung in den wachsenden Oocyten vonMusca domestica untersucht. Sie beginnt nach 30 min im Autoradiogramm sichtbar zu werden. Durch ihre Färbbarkeit und Markierung konnte die Dotterfraktion im Pherogramm von Ovar und Hämolymphe eines mittleren Wachstumsstadiums (Stadium 3) nachgewiesen werden. Nach Abschlu\ der Vitellogenese tritt sie in der Hämolymphe nicht mehr auf. Die Einlagerung der Dotterproteine wird durch Actinomycin gestört, dagegen läuft ihre Synthese nahezu unbeeinflu\t weiter. Die Transporthemmung kann als bisher unbekannter Nebeneffekt des Actinomycins gedeutet werden.
Synthesis of haemolymph proteine and the uptake of the yolk fraction in the oocyte during Actinomycin-treatment. (Studies onMusca domestica)
Summary By means of radioautographic and electrophoretic techniques yolk protein uptake in the growing oocytes ofMusca domestica was investigated. After 30 min yolk protein becomes visible in the radioautograms. By stainability and labeling the yolk fraction could be demonstrated in the pherogram of ovary and haemolymph in an intermediate developmental stage (stage 3). After the end of vitellogenesis it does not appear in the haemolymph. The yolk protein uptake is inhibited by Actinomycin, but the synthesis goes on nearly as normal. This inhibition can be interpretated as a new accessory effect of Actinomycin.相似文献
2.
Summary The influence of O2-deprivation and reduction of temperature on the incorporation of the RNA-precursors 3H-uridine und 3H-cytidine is investigated in various tissues of the larvae and in the ovaries of adults of the housefly Musca domestica L. While RNA-synthesis in most of the tissues is strongly reduced under anaerobic conditions, synthesis continues in a moderate extent in muscle cell nuclei and nurse cell nuclei. The RNA-macromolecules (mRNA and rRNA), however, do not migrate into the cytoplasma. RNA-synthesis within the cell nucleus is less affected by a sudden reduction of temperature than the passage of RNA through the nuclear membrane which is reduced to a very low rate. The macromolecular RNA, therefore, does not diffuse into the cytoplasma but is transported actively through the nuclear envelope. The malformations caused by anaerobiosis during embryogenesis are brought in connexion with the active RNA-transport through the nuclear envelope and the separation of transport and synthesis.
Herrn Professor Dr. Hans Bauer zum 60. Geburtstag gewidmet.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft. 相似文献
Herrn Professor Dr. Hans Bauer zum 60. Geburtstag gewidmet.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft. 相似文献
3.
Zusammenfassung Arbeiterinnen vonMyrmica ruginodis
Nyl. werden im weisellosen Zustand fertil. Sie legen aber keine Eier, wenn sie mehr als 3 Larven je Arbeiterin zu versorgen haben (Mamsch, 1965). Arbeiterinnengruppen wurden mit und ohne Larven von der Königin abgetrennt. In den eierlegenden Gruppen wurde die erneut zugesetzte eigene Königin entweder nicht beachtet oder angegriffen. In den Gruppen, in denen die Arbeiterinnen durch Larvenpflege unfruchtbar blieben, wurde die Königin intensiv beleckt und in das engere Nest eingetragen. Isolierte eierlegende Arbeitergruppen zeigten im Gegensatz zu Arbeiterinnen mit inaktiven Ovarien keine Tendenz, sich mit der Königingruppe zu vereinigen. Das veränderte Verhalten der Arbeiterinnen gegenüber der Königin ist demnach nicht vom Zeitraum der Weisellosigkeit abhängig. Es wurde nur bei eierlegenden Arbeiterinnen beobachtet.
Herrn Prof. Dr.K. Gösswald, zum 60. Geburtstag gewidmet. 相似文献
Summary Workers ofMyrmica ruginodis Nyl. start laying eggs after being separated from their queen. No deposition of eggs occurs in groups in which each worker has to feed 3 or more larvae (Mamsch, 1965). Worker groups rearing larvae and those without brood were separated from the queen.When the queen was put again into an egg-laying worker group, either no attention was paid to her or she was attacked. In groups of workers sterile due to rearing larvae the queen was licked intensively and carried into the nest cavity. Fertile worker groups showed no tendency to join the queen group. The change in the workers' behaviour does not depend on the time of the separation from the queen. It only occurs in groups of fertile workers.
Résumé Des ouvrières deMyrmica ruginodis Nyl. deviennent fertiles après avoir été séparées de la reine. Mais elles ne pondent pas d'ufs, si elles ont chacune trois larves ou plus à nourrir (Mamsch, 1965). Des groupes d'ouvrières, d'une part avec larves et d'autre part sans, ont été séparés de la reine. Les groupes d'ouvrières pondeuses n'attachaient pas d'attention à la reine replacée dans le nid ou encore l'attaquaient. Dans les groupes où les ouvrières étaient restées infertiles à cause du nourrissement du couvain, la reine était léchée d'une façon intensive et portée à l'intérieur du nid. A l'opposé des ouvrières stériles, les groupes d'ouvrières pondeuses isolées ne montraient aucune tendance à joindre le groupe de la reine. Le changement du comportement des ouvrières ne dépend donc pas de la durée de l'état orphelin; il n'est observé que chez les ouvrières pondeuses.
Herrn Prof. Dr.K. Gösswald, zum 60. Geburtstag gewidmet. 相似文献
4.
Raven L. Bier Jennifer J. Mosher Louis A. Kaplan Jinjun Kan 《Environmental microbiology》2023,25(10):1860-1874
A mechanistic understanding of factors that structure spatiotemporal community composition is a major challenge in microbial ecology. Our study of microbial communities in the headwaters of three freshwater stream networks showed significant community changes at the small spatial scale of benthic habitats when compared to changes at mid- and large-spatial scales associated with stream order and catchment. Catchment (which included temperate and tropical catchments) had the strongest influence on community composition followed by habitat type (epipsammon or epilithon) and stream orders. Alpha diversity of benthic microbiomes resulted from interactions between catchment, habitat, and canopy. Epilithon contained relatively more Cyanobacteria and algae while Acidobacteria and Actinobacteria proportions were higher in epipsammic habitats. Turnover from replacement created ~60%–95% of beta diversity differences among habitats, stream orders, and catchments. Turnover within a habitat type generally decreased downstream indicating longitudinal linkages in stream networks while between habitat turnover also shaped benthic microbial community assembly. Our study suggests that factors influencing microbial community composition shift in dominance across spatial scales, with habitat dominating locally and catchment dominating globally. 相似文献
5.
34 persons with G-6-PD deficiency were diagnosed, and the pathological enzyme-variants of red blood cells were characterized according to the recommendations of WHO. We conclude from the differing residual G-6-PD-activities in red blood cells of the propositi and the differing reactivity of the enzyme in kinetic and physicochemical characterizations that a multiple variety of rare pathological G-6-PD variants exists in the GDR. Using the estimated enzymeparameters it was not possible in all cases to compare directly the newly demonstrated G-6-PD variants with cases already described in the literature. In addition, the differing combinations of parameters render a classification more difficult. 相似文献
6.
Two methods, digestion and elution, were used to recover parasitic nematodes from 470 flatfish belonging to species in the family Pleuronectidae. Samples of similar fish were collected from market lots; half of each sample was subjected to digestion, and half was subjected to elution (sedimentation). The edible (flesh) and the inedible (viscera) portions of each fish were analyzed separately. The total number of nematodes recovered by digestion was 1,110, which was not significantly greater than the 922 nematodes recovered by elution. However, digestion recovered 1,062 nematodes of the anisakine genera Anisakis and Phocanema, which are potentially pathogenic for human consumers of raw of semiraw fish. This number is significantly greater than the 608 pathogenic nematodes recovered by elution. Digestion also recovered 242 more nematodes from the edible flesh than did elution. Conversely, more nonpathogenic nematodes were recovered by elution. Approximately half the fish (240) had been collected in Boston markets, and the other half (230) had been collected in San Francisco markets. Fish from San Francisco each contained an average of eight nematodes, and those from Boston contained an average of less than one nematode per fish. 相似文献
7.
By use of a relatively new mixed stationary phase, complete separation of the branched-chain α-keto acids as O-trimethylsilyl-quinoxalinol derivatives is achieved within 10 min by packed column gas chromatography. Precise quantification of less than 5 nmol of α-keto acids in biological samples is possible. In small aqueous samples the α-keto acids are directly derivatized without prior purification. Plasma need only be deproteinized by perchlorate and neutralized before derivatization. Average relative precision for determination of the three main branched-chain α-keto acids is ± 5.8%. 相似文献
8.
9.
In studies where D-(-)-3-hydroxy[4,4,4-2H3]butyrate is employed as isotopic tracer in vivo, we have described a selected ion monitoring, gas-liquid chromatography-mass spectrometry micromethod which measures [2H3] tracer enrichment in 3-hydroxybutyrate and acetoacetate from 300-microliters blood samples. For plasma samples in the physiologic range, intra- and interassay precisions for each ketone averaged better than +/- 1% and +/- 2%, respectively. The use of the method was validated by comparing kinetic data obtained with the above tracer with simultaneous flux data obtained with conventional D-(-)-3-hydroxy[3-14C]butyrate tracer in five fasted rats. 相似文献
10.